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# My favourite IIT-JEE Maths question

Although I'm in Class 12,but I couldn't stop myself from taking a glance at this year's JEE Math's questions. I found this question to be very intriguing and so I thought of sharing it with my Brilliant friends.

For $$a \in R$$ (set of real numbers) , $$a \neq -1$$, $lim_{n \to \infty}\frac{1^a+2^a+ \ldots +n^a}{(n+1)^{a-1}[(na+1)+(na+2)+\ldots+(na+n)]}= \frac{1}{60}$ Then $$a=?$$

Note by Shubham Srivastava
4 years, 1 month ago

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The answers are 7 and $$\frac{-17}{2}$$. The trick here was to first express the limit in form of summation($$\Sigma$$) and then change summation in definite integration($$\int_0^1$$). · 4 years, 1 month ago

Write a comment or ask a question...can you give me the solution · 1 year, 10 months ago

i just did trail and error.... · 4 years, 1 month ago

a=7 is only accepted · 1 year, 4 months ago

I got two answers....a=7 and a= -7/5, but the answer key gives only one. I got a quadratic equation at the end.

Anybody else got the same result? · 4 years, 1 month ago

what's JEE? · 4 years, 1 month ago

It's the most competitive Engineering Entrance Exam in India.It questions on Physics,Chemistry and Mathematics...... · 4 years, 1 month ago

joint entrance examinations · 3 years, 8 months ago

You got it? · 4 years, 1 month ago

how? · 4 years, 1 month ago

a=7 · 4 years, 1 month ago

were there any options given?? · 4 years, 1 month ago

Yes, its a multiple correct answers question. · 4 years, 1 month ago

how to improve maths skill · 2 years, 7 months ago

they really gave such easy questions this year?JEE has been diluted. · 4 years, 1 month ago

Good thing you didn't see the Physics section... · 4 years, 1 month ago

I took a look,and I see no reason of deviating from my stand.I didn't see anything much innovative,except for a hydrostatics problem in paper 1,and a couple of matching type questions in paper 2.Even those were not really tough,just needed keeping your head cool.Trust me,JEE has seen much better days. · 4 years, 1 month ago